Is Intermittent Fasting Healthy or Harmful for Women? By: Xenia Morrison

    

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    Recently, intermittent fasting, the practice of eating only in a specific time frame, has taken charge as the most popular method for weight loss. There are many forms of intermittent fasting, such as the 5:2 method (where a person eats normally for 5 days, then restricts calories for 2 days), and the 18:6 method (fast for 18 hours, then eat within the chosen 6 hour window). The most popular method is the 16:8, where a person fasts for 16 hours and has an 8 hour window where they can eat whatever they wish. As long as a person goes 12 hours without eating, it is considered fasting. The idea behind intermittent fasting is that, by going a long period of time without eating, the body has time to fully digest the food, return to normal blood sugar levels, and manage the hunger hormone, ghrelin, as the body learns to be hungry at specific times of the day (Roeder, 2025). Also, with less energy focused on digesting all the time, the body can focus on repairing cells. Women have been the majority of the population online who have done intermittent fasting. They claim that, since fasting, they have seen significant improvements, including weight loss, decreased hunger, and improved gut health. Others have also seen improvements in their sleep quality, blood pressure, and cognitive performance (Summer). However, there has also been backlash from other studies, arguing that instead of improving hunger levels, intermittent fasting can lead to binge eating (D’Arrigo) and affect menstrual and hormone cycles (Cleveland Clinic). 

 The Downside 

    Although intermittent fasting has several benefits, there have been some studies that overlook how it may have some downsides for women, such as affecting one’s menstrual cycle. It’s not practical for women to fast the same way as men, as it can prevent ovulation from occurring, thus disrupting the menstrual cycle. Cleveland Clinic published an article called, “How Intermittent Fasting Affects Women,” and it references registered dietician, Julia Zumpano, who points out that although fasting is great for some people, it can also negatively affect a woman’s cycle. Zumpano further elaborates on this point, stating that fasting will make the body think that it’s starving, and therefore stop ovulation and affect the overall menstrual cycle, causing symptoms, such as low sex drive, trouble sleeping, acne, and hair loss. However, Cleveland Clinic adds to this by suggesting the 12:12 method for women that have yet to reach menopause, contending that “[P]re-menopausal women may be best served with a low-intensity intermittent fasting schedule, especially at first.” Cleveland Clinic proceeds to give out more tips for women who are interested in gaining benefits from intermittent fasting, by mentioning the best times to fast, like the day one’s period would start as well as the week proceeding it, as well as the time frame where it would be best to step away, or at least ease up on fasting, since that is when estrogen drops, and women experience more stress, exhaustion, and mood swings. 

     In addition to the debate that fasting is not healthy for pre-menopausal women, there have also been studies showing that it is not healthy, both mentally and physically, for women with a history of eating disorders. D’Arrigo contributes to this idea by running a questionnaire for a group of participants to show that intermittent fasting is often practiced by young, vulnerable groups of people, who may form eating disorders or return to previous disordered habits. The questionnaire asked a group of women, men, and non-gender conforming individuals if they have been intermittent fasting for 12 months or one month. It was found that regardless of how long they have been fasting, all groups had higher scores on the Eating Disorder Examination Questionnaire. Women in particular, were found to be associated with all forms of eating disorders after fasting (D’Arrigo, 2023). Harvard Medical School also wrote an article, “4 intermittent fasting side effects to watch out for,” which supports D’Arrigo’s ideas, explaining that fasting can lead to eating disorders such as binge eating because when the body is hungry during the fast, all the brain can think about is eating. It’s most difficult in the beginning, when the body is not used to fasting, and when the person can finally eat, they may overindulge in food since it has been deprived for a long time. Although intermittent fasting can lead to binge eating and may be a result of, as well as result in, eating disorders, people are usually more prone to binging when they limit how much they can eat due to their desire for fast weight loss. To help this from becoming an issue, it is recommended by doing a less intense fast by fasting for only 12 hours at a time (Cleveland Clinic). By doing this, it will help with the mentality, “I’m not allowed to eat yet, I still have to wait a long time” which would result in the brain instinctively fighting back with, “Wait, we are not allowed to eat? Are we starving? The minute this body gets food, we are going to eat everything in sight because we are now mentally in starvation mode.” Not only will fasting for 12 hours help with the scarcity mentality that usually leads to binging, but it will also allow the body to still have time to fully digest food, resulting in less bloating at night as well as in the morning. If the person wants to, they can slowly build up into fasting for longer fragments of time.

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     By bringing these points on how to safely fast, Cleveland Clinic shows that although eating disorders is still a real contender for intermittent fasting, as well as the fact that fasting can impact a woman’s period negatively, there are still ways to gently ease into the practice of fasting by starting off with less intensive fasting cycles, as well as being mindful of the best times to fast so that one can still try it and see if they can gain the benefits from fasting, just as others have claimed. 

 Better Sleep 

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    Fasting also has other benefits that make it worth trying; one of them being improved sleep. Summers explains that, “[F]asting may improve the quality of your sleep by reinforcing your circadian rhythms… Your circadian rhythm primarily relies on sunlight to regulate these functions, but food is a powerful secondary circadian zeitgeber, or ‘time cue’. Following set meal times, as one does during fasting, can help reinforce your natural circadian rhythms.” Since sleep is the time when the body repairs its cells, muscles, and burns fat, having quality rest at night is vital, and fasting can help with this by regulating one’s circadian rhythms. Summers notes that by doing this and providing the body the time it needs to repair those bodily functions, it can also delay aging. Summers also recognizes that intermittent fasting may lead to decreased sleep quality for some people, but it usually only occurs when people break their fast late at night and fill themselves with too much food right before sleep, which can raise one’s body temperature and disrupt one’s sleep. The author contends that it is usually best for people to have their last meal at least 3 hours before going to sleep, so that they will not go to bed hungry, but not bloated either. Although fasting can definitely result in bad sleep quality, it can be easily fixed by further separating dinner time and the time when one would sleep. By ending the meal time earlier, it will result in better sleep, which can lead to better cognitive functions and a better mood as well (Summers). 

Fasting for Night Shift Workers 

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     Consequently, when a person does not follow their natural circadian rhythm, like night shift workers for example, this can lead to a risk of developing health issues such as severe weight gain and type 2 diabetes. Although fasting has been noted to help with these issues, Harvard Professor of Nutrition, Courtney Peterson, discloses that fasting may not be the solution for shift workers, as they don’t have adequate breaks for them to eat during their window (Roeder, 2025). However, this only reigns true for CER fasting, such as the 16:8 and the 12:12 method, where the person is restricted within the same eating window everyday. In a peer reviewed study, Bonham et al. observed a group of randomized night shift workers, ages 25-65. These workers were told to follow the 5:2 method, by eating 2100 kJ (about 500 calories) on 2 of their days off and eating normally on the other 5 nights when they work (IF:2D). The participants did this for 24 weeks, and at the end, it was noted that, “[T]hose randomized to IF:2D had lower and total cholesterol compared to CER… In a completer’s analysis, favourable changes in body weight, insulin resistance, body composition, blood pressure, and cardiometabolic markers were observed within all groups,” (1). This shows that although other methods of CER fasting may not be ideal for night shift workers, the 5:2 method offers a way for them to still fast and reap the benefits.

 Personal Opinion

     From my standpoint, I believe that fasting is a great method, because not only does it help me lose weight, but I found that I felt better physically and mentally in my day to day life. I started fasting when I first began wrestling in high school, purely as a way to lose weight. Truthfully, I didn’t do much research, and went with the 16:8 method because that’s what my peers suggested for me to do. Since I was a big breakfast person, I would break my fast at 9 A.M. and was able to eat until 5 P.M.. I found significant benefits from this, including better sleep as Summers has mentioned, because I would have an early dinner and have lots of time to digest between my last meal and sleeping. I liked that I would wake up and not feel as bloated as I did before fasting, which helped improve my digestion. It helped me feel more hungry in the morning, as well as less hungry at night. Similarly, I also lost 5 pounds from doing this, which may not be much, but my increase in muscle mass made up for the loss in fat In conclusion, intermittent fasting can be an excellent method for becoming a healthier person, as long as the person takes precautions with how long they are fasting. For people who may be pre-diabetic, struggling with their hunger levels, blood pressure, or are looking to lose weight, they may see lots of positive outcomes. However, it’s very important to break one’s fast with nutrient-dense foods, stay hydrated during and after the fast, as well as not fasting to the extreme. Going too long without food, or breaking the fast with minimal calories can result in bingeing, and the person may develop an eating disorder, or return to their previous disordered habits, and gain even more undesired weight in the process.

Works Cited

Bonham et al. Intermittent fasting for weight loss in night shift workers: a three-arm, superiority randomised clinical trial, vol. 117. Science Direct. 18 June, 2025. Intermittent fasting for weight loss in night shift workers: a three-arm, superiority randomised clinical trial - ScienceDirect. Accessed 28 February, 2026.

D’Arrigo, Terri. Intermittent Fasting Linked to Eating Disorder Behaviors, vol. 58, no. 2. Psychiatry Online. 26 January, 2023. Intermittent Fasting Linked to Eating Disorder Behaviors | Psychiatric News Accessed 28 February, 2026.

4 intermittent fasting side effects to watch out for. Harvard Health Publishing. 

4 intermittent fasting side effects to watch out for - Harvard Health Accessed 28 February, 2026

How Intermittent Fasting Affects Women. Cleveland Clinic. 17 July, 2023. 

Is Intermittent Fasting Healthy for Women? Accessed 28 February, 2026.

Roeder, Amy. The health benefits of intermittent fasting. Harvard T.H. Chan. 24 September, 2025. The health benefits of intermittent fasting | Harvard T.H. Chan School of Public Health Accessed 28 February, 2026.

Summer, J. V. Why Intermittent Fasting Can Lead to Better Sleep. Sleep Foundation. 15 July, 2025. The Benefits of Intermittent Fasting for Sleep Accessed 28 February, 2026.